<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script src="vue.js"></script>
	</head>
	<body>

		<div id="app">

			<span v-if="isUser">
				<label for="username">用户账号</label>
				<input type="text" id="username" placeholder="用户名" key="username">
			</span>

			<span v-else>
				<label for="email">用户邮箱</label>
				<input type="text" id="email" placeholder="用户邮箱" key="email">
			</span>

			<button @click="isUser = !isUser">切换类型</button>

		</div>

		<script>
			new Vue({
				el: '#app',
				data: {
					isUser: true
				}
			});
		</script>

	</body>
</html>
